Fall SemeSter 2025 | UniverSity oF SoUth
aFrica (UniSa) | PSc1501 – Practical Science
For the claSSroom | november/December 2025
exam Pack | comPrehenSive noteS, aSSignmentS
& StUDy gUiDe For FUtUre eDUcatorS
Question 1:
What is the primary purpose of conducting a controlled experiment in a scientific
study?
A) To ensure that the results are easily replicable
B) To isolate the effect of the independent variable
C) To increase the complexity of the data analysis
D) To validate the hypothesis without testing it
Correct Answer: B) To isolate the effect of the independent variable
Rationale: Controlled experiments are designed to test the effect of one variable at a
time while keeping other variables constant. This isolation allows scientists to
determine if changes in the independent variable cause changes in the dependent
variable.
Question 2:
Which of the following is an example of a qualitative observation?
A) The solution is 0.5 M in concentration
B) The temperature of the liquid is 25°C
C) The liquid is blue in color
D) The mass of the solid is 10 grams
Correct Answer: C) The liquid is blue in color
Rationale: Qualitative observations describe characteristics or qualities that cannot be
measured numerically. In this case, the color of the liquid is a qualitative observation,
while the other options involve quantitative measurements.
Question 3:
Which of the following best describes the scientific method?
A) A linear process of steps to reach a conclusion
B) A flexible and iterative approach to inquiry
C) A systematic process that includes observation, hypothesis, experimentation,
and conclusion
D) A method that relies solely on theoretical assumptions
,Correct Answer: C) A systematic process that includes observation, hypothesis,
experimentation, and conclusion
Rationale: The scientific method is a structured approach to scientific inquiry that
involves making observations, forming hypotheses, conducting experiments, and
drawing conclusions based on the data collected.
Question 4:
What is the role of a hypothesis in scientific research?
A) To provide a definitive answer to a scientific question
B) To propose a testable explanation for a phenomenon
C) To summarize the findings of an experiment
D) To establish a theory without testing
Correct Answer: B) To propose a testable explanation for a phenomenon
Rationale: A hypothesis is an educated guess that offers a possible explanation for an
observation. It must be testable through experimentation to be validated or refuted.
Question 5:
Which of the following is a characteristic of a good scientific theory?
A) It is based on personal beliefs
B) It cannot be modified or disproved
C) It is supported by a large body of evidence
D) It is derived from a single experiment
Correct Answer: C) It is supported by a large body of evidence
Rationale: A good scientific theory is well-supported by extensive evidence from
multiple experiments and observations, allowing it to explain and predict phenomena in
the natural world.
Question 6:
What is the primary reason for using control groups in experiments?
A) To increase sample size
B) To provide a baseline for comparison
C) To test multiple hypotheses simultaneously
D) To eliminate all variables
Correct Answer: B) To provide a baseline for comparison
Rationale: Control groups are essential in experiments as they allow researchers to
,compare the effects of the independent variable with a group that does not receive the
treatment, helping to isolate the variable's effect.
Question 7:
Which of the following best describes the term "variable" in scientific research?
A) A fixed component of an experiment
B) Any factor that can change or be changed
C) The final outcome of an experiment
D) The hypothesis being tested
Correct Answer: B) Any factor that can change or be changed
Rationale: Variables are any elements that can be manipulated or measured in an
experiment. They include independent variables (changed) and dependent variables
(measured).
Question 8:
In an experiment testing the effect of sunlight on plant growth, what would be the
independent variable?
A) Amount of sunlight
B) Type of plant
C) Soil quality
D) Watering frequency
Correct Answer: A) Amount of sunlight
Rationale: The independent variable is the factor that is manipulated in the experiment.
In this case, the amount of sunlight is what is being changed to observe its effect on
plant growth.
Question 9:
What is the main purpose of peer review in scientific research?
A) To increase the number of publications
B) To ensure the quality and credibility of research
C) To promote collaboration among scientists
D) To expedite the publication process
Correct Answer: B) To ensure the quality and credibility of research
Rationale: Peer review helps validate research by having other experts in the field
evaluate the methodology, results, and conclusions before publication, thereby
maintaining scientific integrity.
, Question 10:
Which of the following statements is true about scientific theories?
A) They can never be changed or updated
B) They are just educated guesses
C) They are based on extensive evidence and can be modified with new data
D) They are the same as hypotheses
Correct Answer: C) They are based on extensive evidence and can be modified with
new data
Rationale: Scientific theories are comprehensive explanations supported by a
substantial amount of evidence. They can evolve as new data emerges, reflecting the
dynamic nature of scientific understanding.
Question 11:
What is the significance of replicating experiments in scientific research?
A) To decrease the likelihood of errors
B) To confirm the reliability and validity of results
C) To make the experiment more complex
D) To test as many variables as possible
Correct Answer: B) To confirm the reliability and validity of results
Rationale: Replication of experiments is crucial for verifying results. It helps establish
that findings are consistent and not due to chance or experimental error.
Question 12:
Which type of data is measured using numerical values?
A) Qualitative data
B) Quantitative data
C) Descriptive data
D) Anomalous data
Correct Answer: B) Quantitative data
Rationale: Quantitative data refers to information that can be expressed in numerical
form, allowing for statistical analysis, whereas qualitative data is descriptive and cannot
be measured numerically.
Question 13:
aFrica (UniSa) | PSc1501 – Practical Science
For the claSSroom | november/December 2025
exam Pack | comPrehenSive noteS, aSSignmentS
& StUDy gUiDe For FUtUre eDUcatorS
Question 1:
What is the primary purpose of conducting a controlled experiment in a scientific
study?
A) To ensure that the results are easily replicable
B) To isolate the effect of the independent variable
C) To increase the complexity of the data analysis
D) To validate the hypothesis without testing it
Correct Answer: B) To isolate the effect of the independent variable
Rationale: Controlled experiments are designed to test the effect of one variable at a
time while keeping other variables constant. This isolation allows scientists to
determine if changes in the independent variable cause changes in the dependent
variable.
Question 2:
Which of the following is an example of a qualitative observation?
A) The solution is 0.5 M in concentration
B) The temperature of the liquid is 25°C
C) The liquid is blue in color
D) The mass of the solid is 10 grams
Correct Answer: C) The liquid is blue in color
Rationale: Qualitative observations describe characteristics or qualities that cannot be
measured numerically. In this case, the color of the liquid is a qualitative observation,
while the other options involve quantitative measurements.
Question 3:
Which of the following best describes the scientific method?
A) A linear process of steps to reach a conclusion
B) A flexible and iterative approach to inquiry
C) A systematic process that includes observation, hypothesis, experimentation,
and conclusion
D) A method that relies solely on theoretical assumptions
,Correct Answer: C) A systematic process that includes observation, hypothesis,
experimentation, and conclusion
Rationale: The scientific method is a structured approach to scientific inquiry that
involves making observations, forming hypotheses, conducting experiments, and
drawing conclusions based on the data collected.
Question 4:
What is the role of a hypothesis in scientific research?
A) To provide a definitive answer to a scientific question
B) To propose a testable explanation for a phenomenon
C) To summarize the findings of an experiment
D) To establish a theory without testing
Correct Answer: B) To propose a testable explanation for a phenomenon
Rationale: A hypothesis is an educated guess that offers a possible explanation for an
observation. It must be testable through experimentation to be validated or refuted.
Question 5:
Which of the following is a characteristic of a good scientific theory?
A) It is based on personal beliefs
B) It cannot be modified or disproved
C) It is supported by a large body of evidence
D) It is derived from a single experiment
Correct Answer: C) It is supported by a large body of evidence
Rationale: A good scientific theory is well-supported by extensive evidence from
multiple experiments and observations, allowing it to explain and predict phenomena in
the natural world.
Question 6:
What is the primary reason for using control groups in experiments?
A) To increase sample size
B) To provide a baseline for comparison
C) To test multiple hypotheses simultaneously
D) To eliminate all variables
Correct Answer: B) To provide a baseline for comparison
Rationale: Control groups are essential in experiments as they allow researchers to
,compare the effects of the independent variable with a group that does not receive the
treatment, helping to isolate the variable's effect.
Question 7:
Which of the following best describes the term "variable" in scientific research?
A) A fixed component of an experiment
B) Any factor that can change or be changed
C) The final outcome of an experiment
D) The hypothesis being tested
Correct Answer: B) Any factor that can change or be changed
Rationale: Variables are any elements that can be manipulated or measured in an
experiment. They include independent variables (changed) and dependent variables
(measured).
Question 8:
In an experiment testing the effect of sunlight on plant growth, what would be the
independent variable?
A) Amount of sunlight
B) Type of plant
C) Soil quality
D) Watering frequency
Correct Answer: A) Amount of sunlight
Rationale: The independent variable is the factor that is manipulated in the experiment.
In this case, the amount of sunlight is what is being changed to observe its effect on
plant growth.
Question 9:
What is the main purpose of peer review in scientific research?
A) To increase the number of publications
B) To ensure the quality and credibility of research
C) To promote collaboration among scientists
D) To expedite the publication process
Correct Answer: B) To ensure the quality and credibility of research
Rationale: Peer review helps validate research by having other experts in the field
evaluate the methodology, results, and conclusions before publication, thereby
maintaining scientific integrity.
, Question 10:
Which of the following statements is true about scientific theories?
A) They can never be changed or updated
B) They are just educated guesses
C) They are based on extensive evidence and can be modified with new data
D) They are the same as hypotheses
Correct Answer: C) They are based on extensive evidence and can be modified with
new data
Rationale: Scientific theories are comprehensive explanations supported by a
substantial amount of evidence. They can evolve as new data emerges, reflecting the
dynamic nature of scientific understanding.
Question 11:
What is the significance of replicating experiments in scientific research?
A) To decrease the likelihood of errors
B) To confirm the reliability and validity of results
C) To make the experiment more complex
D) To test as many variables as possible
Correct Answer: B) To confirm the reliability and validity of results
Rationale: Replication of experiments is crucial for verifying results. It helps establish
that findings are consistent and not due to chance or experimental error.
Question 12:
Which type of data is measured using numerical values?
A) Qualitative data
B) Quantitative data
C) Descriptive data
D) Anomalous data
Correct Answer: B) Quantitative data
Rationale: Quantitative data refers to information that can be expressed in numerical
form, allowing for statistical analysis, whereas qualitative data is descriptive and cannot
be measured numerically.
Question 13:
